The present invention relates to a water tank for mass storage; and, more particularly, to a stainless water tank manufactured by assembling without welding.
Conventionally, a water tank storing more than 10 tons of water has been made of thick steel plates or plastic materials such as fiber reinforced plastic (FRP). However, the water tank made of steel plates has a demerit that the water stored therein is contaminated by rust and the water tank made of FRP has a demerit that it is weak against external shock. Therefore, water tanks for mass storage are recently made of stainless steel that has anti-rust characteristics.
FIG. 1 shows a conventional stainless water tank 1 that is of a rectangular parallelopiped shape and is made of stainless steel panels 2. The water tank comprises wall portions formed by welding a number of stainless steel panels 2 and a plurality of reinforcing members 3 which are welded in the water tank transversally and longitudinally in order to increase the structural strength of the stainless steel panel 2. The water tank has a manhole 4 on the upper side thereof and a drain hole 5 on the lower side thereof as shown in FIG. 2.
As shown in FIG. 2, each of the stainless steel panel 2 has folded portions 2a which protrude to an inside of the water tank and the folded portions 2a of adjacent stainless panels 2 are welded together, thereby forming the water tank.
However, since a number of stainless steel panels 2 are welded from the inside of the water tank 1 and a plurality of the reinforcing members 3 are welded in the water tank transversally and longitudinally for manufacturing such conventional water tank, lots of time is required and high-priced welding equipments and skilled persons are needed, thereby increasing manufacturing cost.
Further, although stainless steel has anti-rust characteristics, the mechanical properties thereof sharply deteriorate when it is welded and the brittleness of the welded portions increases. Therefore, cracks may develop at the welded portions of the water tank or rust can be formed at the welded portions, thereby contaminating water stored in the water tank.
As shown in FIG. 2, since a bottom surface of the water tank 1 is flat and the folded portions of the stainless steel panels 2a protrude therefrom, the water stored in the water tank is not completely drained and a small amount of water remains with sediments on the bottom surface of the water tank. Thus, the remaining water and sediments are removed by using a suction pipe connected to a suction pump. However, the reinforcing members 3 limit space available for working in the water tank, thereby making the removing operation cumbersome and increasing the occurrences of accidents.
Further, since the water tank has a flat top surface, chroline gas included in the tap water cannot be exhausted from the water tank and remains in an upper portion of the inside of the water tank, thereby corroding the upper surface of the water tank.
Furthermore, since the water tank is of a rectangular parellelopiped shape, the water tank can be broken by a localized pressure increase generated by uneven installation thereof.
It is, therefore, an object of the present invention to provide a stainless water tank of a cylindrical shape which can be manufactured without welding and easily installed, thereby preventing rust development and facilitating draining and cleaning.
In accordance with a preferred embodiment of the present invention, there is provided a water tank comprising a body, a top part and a bottom part, wherein each of the body, the top part and the bottom part includes
a plurality of stainless steel panels having connecting portions with a number of holes and extruding to an outside of the water tank;
a plurality of packing members disposed between folded portions of the stainless steel panels; and
coupling members inserted into the holes formed on the folded portions and coupling the stainless steel panels.
In accordance with another preferred embodiment of the present invention, there is provided a water tank made of stainless steel that is of a substantially cylindrical shape, comprising:
a plurality of curved stainless steel panels, the curved stainless steel panels being coupled together to form a substantially cylindrical body of the water tank, each of the curved stainless steel panels including a number of holes and a first connecting portion extruded to an outside of the water tank;
a plurality of fan-shaped stainless steel panels being disposed at an upper portion and a lower portion to form a cone-shaped top part and a cone-shaped bottom part of the water tank, respectively, each of the fan-shaped stainless steel panels including a number of holes and a first connecting portion extruding to the outside of the water tank;
a plurality of packing members being inserted between the first and the second connecting portions;
a plurality of reinforcing members, each having an L-shaped cross-section and a number of holes on one side portion and being arranged on both side of the first and the second connecting portion;
a number of bolts and nuts for coupling the curved stainless steel panels, fan-shaped stainless steel panels and the reinforcing members together by being inserted into the holes formed on the first connecting portions, the second connecting portions and the reinforcing members;
a plurality of reinforcing bars, both end portions of each of the reinforcing bars being fixed to the fan-shaped stainless steel panel forming the top part and the fan-shaped stainless steel panel forming the bottom part, respectively;
an air vent disposed on a center portion of the top part which is of a cone-shape and includes the fan-shaped stainless steel panels; and
a drain pipe disposed on the center portion of the bottom part which is of a cone-shape and includes the fan-shaped stainless steel panels.